Dry non-plasma treatment system and method of using

ABSTRACT

A dry non-plasma treatment system and method for removing oxide material is described. The treatment system is configured to provide chemical treatment of one or more substrates, wherein each substrate is exposed to a gaseous chemistry under controlled conditions including surface temperature and gas pressure. Furthermore, the treatment system is configured to provide thermal treatment of each substrate, wherein each substrate is thermally treated to remove the chemically treated surfaces on each substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims the benefit of priorityunder 35 USC §120 from U.S. Ser. No. 11/425,883, filed Jun. 22, 2006.This application is related to pending U.S. patent application Ser. No.10/705,200, entitled “Processing System and Method for ChemicallyTreating a Substrate”, filed on Nov. 12, 2003; pending U.S. patentapplication Ser. No. 10/704,969, entitled “Processing System and Methodfor Thermally Treating a Substrate”, filed on Nov. 12, 2003; pendingU.S. patent application Ser. No. 10/705,201, entitled “Processing Systemand Method for Treating a Substrate”, filed on Nov. 12, 2003; pendingU.S. patent application Ser. No. 11/390,470, entitled “Batch ProcessingSystem and Method for Performing Chemical Oxide Removal”, filed on Mar.28, 2006; pending U.S. patent application Ser. No. 10/859,975, entitled“Method of Operating a Processing System for Treating a Substrate”,filed on Jun. 4, 2004; and pending U.S. patent application Ser. No.10/860,149, entitled “Processing System and Method for Treating aSubstrate”, filed on Jun. 4, 2004. The entire contents of all of theseapplications are herein incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dry non-plasma treatment system andmethod for treating a substrate, and more particularly to a drynon-plasma treatment system and method for chemical and thermaltreatment of a substrate.

2. Description of Related Art

In material processing methodologies, pattern etching comprises theapplication of a thin layer of light-sensitive material, such asphotoresist, to an upper surface of a substrate, that is subsequentlypatterned in order to provide a mask for transferring this pattern tothe underlying thin film during etching. The patterning of thelight-sensitive material generally involves exposure by a radiationsource through a reticle (and associated optics) of the light-sensitivematerial using, for example, a micro-lithography system, followed by theremoval of the irradiated regions of the light-sensitive material (as inthe case of positive photoresist), or non-irradiated regions (as in thecase of negative resist) using a developing solvent.

Additionally, multi-layer and hard masks can be implemented for etchingfeatures in a thin film. For example, when etching features in a thinfilm using a hard mask, the mask pattern in the light-sensitive layer istransferred to the hard mask layer using a separate etch step precedingthe main etch step for the thin film. The hard mask can, for example, beselected from several materials for silicon processing including silicondioxide (SiO₂), silicon nitride (Si₃N₄), and carbon, for example.

In order to reduce the feature size formed in the thin film, the hardmask can be trimmed laterally using, for example, a two-step processinvolving a chemical treatment of the exposed surfaces of the hard masklayer in order to alter the surface chemistry of the hard mask layer,and a post treatment of the exposed surfaces of the hard mask layer inorder to desorb the altered surface chemistry.

SUMMARY OF THE INVENTION

The present invention relates to a dry non-plasma treatment system andmethod for treating a substrate, and to a dry non-plasma treatmentsystem and method for chemically and thermally treating a substrate.

In one embodiment, a treatment system for removing material on asubstrate is described. The treatment system comprises: a temperaturecontrolled process chamber configured to contain a substrate andconfigured to facilitate a non-plasma environment; a temperaturecontrolled substrate holder mounted within the temperature controlledprocess chamber, and configured to support the substrate and configuredto control a temperature of the substrate when the substrate is restingon an upper surface of the temperature controlled substrate holder; avacuum pumping system coupled to the temperature controlled processchamber; a chemical treatment system coupled to the temperaturecontrolled process chamber and configured to introduce a process gas tothe temperature controlled process chamber, wherein the process gaschemically alters exposed surface layers on the substrate; a thermaltreatment system, separate from the temperature-controlled substrateholder, coupled to the temperature controlled process chamber andconfigured to elevate the temperature of the substrate in thetemperature controlled process chamber, wherein the elevated temperaturecauses evaporation of the chemically altered surface layers; and acontroller coupled to the temperature controlled substrate holder, thechemical treatment system, and the thermal treatment system andconfigured to control the amount of the process gas introduced to thesubstrate, and the temperature to which the substrate is set.

In another embodiment, a method of removing material on a substrate isdescribed. The method comprises: disposing a substrate on a temperaturecontrolled substrate holder mounted within a temperature controlledprocess chamber, the temperature controlled process chamber configuredto facilitate a non-plasma environment, and the temperature controlledsubstrate holder configured to support the substrate and configured tocontrol a temperature of the substrate when the substrate is resting onan upper surface of the temperature controlled substrate holder;evacuating the temperature controlled process chamber using a pumpingsystem coupled to the temperature controlled process chamber; chemicallytreating the substrate using a chemical treatment system coupled to thetemperature controlled process chamber by exposing the substrate to aprocess gas composition selected to chemically alter exposed surfacelayers on the substrate; and following the chemical treating, thermallytreating the substrate using a thermal treatment system, separate fromthe temperature-controlled substrate holder, coupled to the temperaturecontrolled process chamber by heating the substrate to a temperaturesufficient to cause evaporation of the chemically altered surfacelayers.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 presents a block diagram of a dry non-plasma treatment system forperforming a chemical oxide removal process according to an embodimentof the present invention;

FIG. 2 presents a dry non-plasma treatment system for performing a dry,non-plasma chemical removal process according to another embodiment ofthe present invention;

FIGS. 3A and 3B present a substrate holder for performing a dry,non-plasma chemical removal process according to another embodiment ofthe present invention;

FIGS. 4A and 4B present a substrate holder for performing a dry,non-plasma chemical removal process according to another embodiment ofthe present invention; and

FIG. 5 presents a flow chart of a method of performing a dry, non-plasmachemical removal process according to an embodiment of the presentinvention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the following description, for purposes of explanation and notlimitation, specific details are set forth, such as a particulargeometry of the treatment system and descriptions of various componentsand processes. However, it should be understood that the invention maybe practiced in other embodiments that depart from these specificdetails.

According to one embodiment, FIG. 1 presents a treatment system 101 forprocessing a substrate using a dry, non-plasma, treatment process, suchas a chemical oxide removal process, to, for example, trim an oxide maskor remove native oxide or remove a SiO_(x)-containing residue. Forexample, the treatment system 101 is configured to facilitate a chemicaltreatment process during which oxide material on the substrate ischemically altered and a thermal treatment process during whichchemically altered substrate material is desorbed.

FIG. 1 presents a block diagram of a treatment system 101 for treatingthe oxide material on a substrate. Treatment system 101 includes aprocess chamber 110 configured to process the substrate, a chemicaltreatment system 120 coupled to the process chamber 110 and configuredto introduce a process gas to the substrate mounted in process chamber110, a thermal treatment system 130 coupled to process chamber 110 andconfigured to elevate the temperature of the substrate, and a controller150 coupled to the process chamber 110, the chemical treatment system120 and the thermal treatment system 130, and configured to control thetreatment system 101 according to a process recipe.

For example, the chemical treatment system 120 is configured tointroduce a process gas comprising a first gaseous component having asan incipient ingredient HF and an optional second gaseous componenthaving as an incipient ingredient ammonia (NH₃). The two gaseouscomponents may be introduced together, or independently of one another.For example, independent gas/vapor delivery systems may be used tointroduce each gaseous component. Additionally, the chemical treatmentsystem 120 can further include a temperature control system forelevating the temperature of the vapor delivery system in order toprevent the condensation of process vapor therein.

Additionally, either gaseous component, or both, can be introduced witha carrier gas, such as an inert gas. The inert gas can comprise a noblegas, such as argon. Of course, other gasses can also be included in theprocess gas. The chemical treatment of the oxide material on thesubstrate by exposing this material to the two gaseous components causesa chemical alteration of the oxide material surface to a self-limitingdepth. During the chemical treatment of the oxide material on thesubstrate, the substrate temperature can be controlled. For example, thesubstrate temperature can be set to a chemical treatment temperatureless than 100 degrees C.

Referring still to FIG. 1, the thermal treatment system 130 can elevatethe temperature of the substrate to a temperature above the chemicaltreatment temperature, or a temperature range from approximately 50degrees C. to approximately 450 degrees C., and desirably, the substratetemperature can range from approximately 100 degrees C. to approximately300 degrees C. For example, the substrate temperature may range fromapproximately 100 degrees C. to approximately 200 degrees C. The thermaltreatment of the chemically altered oxide surface layers causes theevaporation of these surface layers.

Controller 150 includes a microprocessor, memory, and a digital I/O port(potentially including D/A and/or ND converters) capable of generatingcontrol voltages sufficient to communicate and activate inputs to theprocess chamber 110, the chemical treatment system 120 and the thermaltreatment system as well as monitor outputs from these systems. Aprogram stored in the memory is utilized to interact with the systems120 and 130 according to a stored process recipe.

Alternately, or in addition, controller 150 can be coupled to a one ormore additional controllers/computers (not shown), and controller 150can obtain setup and/or configuration information from an additionalcontroller/computer.

In FIG. 1, singular processing elements (120 and 130) are shown, butthis is not required for the invention. The processing system 101 cancomprise any number of processing elements having any number ofcontrollers associated with them in addition to independent processingelements.

The controller 150 can be used to configure any number of processingelements (120 and 130), and the controller 150 can collect, provide,process, store, and display data from processing elements. Thecontroller 150 can comprise a number of applications for controlling oneor more of the processing elements. For example, controller 150 caninclude a graphic user interface (GUI) component (not shown) that canprovide easy to use interfaces that enable a user to monitor and/orcontrol one or more processing elements.

The processing system 101 can also comprise a pressure control system(not shown). The pressure control system can be coupled to theprocessing chamber 110, but this is not required. In alternateembodiments, the pressure control system can be configured differentlyand coupled differently. The pressure control system can include one ormore pressure valves (not shown) for exhausting the processing chamber110 and/or for regulating the pressure within the processing chamber110. Alternately, the pressure control system can also include one ormore pumps (not shown). For example, one pump may be used to increasethe pressure within the processing chamber, and another pump may be usedto evacuate the processing chamber 110. In another embodiment, thepressure control system can comprise seals for sealing the processingchamber.

Furthermore, the treatment system 101 can comprise an exhaust controlsystem. The exhaust control system can be coupled to the processingchamber 110, but this is not required. In alternate embodiments, theexhaust control system can be configured differently and coupleddifferently. The exhaust control system can include an exhaust gascollection vessel (not shown) and can be used to remove contaminantsfrom the processing fluid. Alternately, the exhaust control system canbe used to recycle the processing fluid.

Referring now to FIG. 2, a simplified block diagram of a treatmentsystem 200 is shown according to another embodiment. The treatmentsystem 200 comprises a treatment chamber 210, a temperature controlledsubstrate holder 220 configured to be substantially thermally isolatedfrom the treatment chamber 210 and configured to support a substrate225, a vacuum pumping system 250 coupled to the treatment chamber 210 toevacuate the treatment chamber 210, a chemical distribution system 240coupled to treatment chamber 210 and configured to introduce a processgas into a process space 245 in order to chemically treat substrate 225,and a radiative heating system 230 coupled to treatment chamber 210 andconfigured to thermally treat substrate 225. Substrate 225 can betransferred into and out of treatment chamber 210 through via asubstrate transfer system (not shown) through a transfer opening (notshown).

The chemical distribution system 240 is configured to introduce aprocess gas configured to, for example, chemically alter oxide materialon substrate 225. The chemical distribution system 240 is configured tointroduce one or more process gases including, but not limited to, HF,NH₃, N₂, H₂, O₂, CO, CO₂, NO, NO₂, N₂O, C_(x)F_(y) (where x, y areintegers), C_(x)H_(z)F_(y) (where x, y, z are integers), etc. Forexample, the process gas can comprise a first gaseous component havingas an incipient ingredient HF and an optional second gaseous componenthaving as an incipient ingredient ammonia (NH₃). The two gaseouscomponents may be introduced together, or independently of one anotherusing a gas supply system 242. For example, independent gas/vapor supplysystems may be used to introduce each gaseous component. Additionally,the chemical distribution system 240 can further include a temperaturecontrol system for elevating the temperature of the chemicaldistribution system 240 in order to prevent the condensation of processvapor therein. Additionally, either gaseous component, or both, can beintroduced with a carrier gas, such as an inert gas. The inert gas cancomprise a noble gas, such as argon. Of course, other gaseous can alsobe included.

As illustrated in FIG. 2, the chemical distribution system 240 can bearranged beyond a peripheral edge of substrate 225. The chemicaldistribution system 240 may comprise a plurality of injection orifices,or nozzles, distributed about the circumference of process space 245.Additionally, alternating groups of one or more orifices, or nozzles,may be used to independently introduce each gaseous component, e.g., HFand ammonia. Alternatively, the chemical distribution system 240 can bearranged within the radiative heating system 230. Alternatively, thechemical distribution system 240 can be arranged within an upperassembly above substrate 225, while radiative heating system 230 islocated beyond a peripheral edge of the chemical distribution system 240yet within view of substrate 225. Chemical distribution system 240 canbe a multi-zone fluid distribution system to adjust the flow of processgas to multiple zones within treatment chamber 210.

Additionally, the radiative heating system 230 is configured to heatsubstrate 225 in order to, for example, desorb chemically altered oxidematerial on substrate 225. The radiative heating system 230 can compriseone or more heat lamps. Each heat lamp may, for example, include atungsten-halogen lamp. Heat lamps, arranged in groups of one or morelamps, may be utilized to spatially adjust the heating of substrate 225.The radiative heating system 230 further comprises a window that isconfigured to preserve the vacuum conditions in process chamber 210 andthat is substantially transparent to infrared (IR) electromagnetic (EM)radiation. For example, the window may comprise quartz or desirablysapphire. Although, the window (when fabricated of quartz) may beconsumed in the dry non-plasma process, the thickness may be selected tobe sufficiently thick to reduce the frequency of its replacement and theassociated replacement costs.

Referring still to FIG. 2, the substrate holder 220 comprises asubstrate temperature control system 260 configured to perform at leastone of monitoring, adjusting or controlling or a combination of two ormore thereof, the temperature of substrate holder 220 or substrate 225or both. For example, the substrate holder 220 and substrate temperaturecontrol system 260 may comprise a substrate clamping system (i.e.,electrical or mechanical clamping system) to improve thermal contactbetween substrate 225 and substrate holder 220, a heating system, acooling system, a substrate backside gas supply system for improvedthermal conductance between the substrate 225 and the substrate holder220, a temperature sensor, etc.

Additionally, the substrate holder 220 comprises a substrate lift system262 including a lift pin assembly (not shown) capable of raising andlowering three or more lift pins in order to vertically transfersubstrate 225 to and from an upper surface of the substrate holder 220and a transfer plane in the process chamber 210, and to verticallytransfer substrate 225 to and from an upper surface of the substrateholder 220 and a heating plane in the process chamber 210. Furthermore,the substrate holder 220 can comprise a backside gas supply system 264configured to supply gas to the backside of substrate 225.

During chemical treatment of substrate 225, substrate 225 rests onsubstrate holder 220 and the temperature is controlled to a chemicaltreatment temperature less than approximately 100 degrees C. while thesubstrate 225 is exposed to process gas configured to chemically alteroxide material on substrate 225. During chemical treatment, substrate225 may be clamped to the substrate holder 220 and a flow of backsidegas can be initiated from a backside gas supply system 264 to affectimproved thermal conductance between the substrate 225 and the substrateholder 220.

Following the chemical treatment of substrate 225, the temperature ofsubstrate 225 is elevated using radiative heating system 230 in order todesorb the chemically altered oxide material. During the thermaltreatment of substrate 225, the substrate 225 can be raised abovesubstrate holder 220 and displaced from the substrate holder 220 to theheating plane using substrate lift system 262 by a distance sufficientto substantially thermally decouple the substrate 225 from substrateholder 220. Furthermore, the substrate 225 may be lifted to closeproximity with the radiative heating system 230 in order to reduce theextent to which other chamber components see the radiative heatingsystem 230 during heating. Preferably, substrate 225 is heated whileother chamber components are not. Additionally, when substrate 225 israised above substrate holder 220, an optional flow of purge gas frombackside gas supply system 264 can be conducted in order to reducecontamination of the backside of substrate 225 during the desorptionprocess.

Referring now to FIGS. 3A, 3B, 4A and 4B, a substrate holder assembly300 is depicted according to another embodiment. The substrate holderassembly 300 comprises substrate holder 320 configured to supportsubstrate 325 and configured to be coupled to process chamber 310. Thesubstrate holder assembly 300 further comprises an electrostaticclamping (ESC) system 380 having a clamp electrode 382 configured toelectrically clamp substrate 225 to substrate holder 220.

Additionally, the substrate holder assembly 300 comprises a substratetemperature control system 360. The substrate temperature control system360 includes a heat exchanger configured to circulate a heat transferfluid through a fluid channel 366 disposed in substrate holder 320 bysupplying the heat transfer fluid through an inlet fluid supply line 362and receiving the heat transfer fluid through an outlet fluid supplyline 363. By adjusting the fluid temperature in the heat exchanger, thetemperature of substrate holder 320 can be adjusted. Although only asingle zone fluid circulation system is shown, the circulation systemmay comprise multiple fluid zones.

Furthermore, the substrate holder assembly 300 comprises a substratelift system 370 including a lift pin assembly capable of raising andlowering three or more lift pins in order to vertically transfersubstrate 325 to and from an upper surface of the substrate holder 320and a transfer plane in the process chamber 310.

In the lift pin assembly, substrate lift pins 372 can be coupled to acommon lift pin element, and can be lowered to below the upper surfaceof substrate holder 320. A drive mechanism utilizing, for example, anelectric drive system (having an electric stepper motor and threadedrod) or a pneumatic drive system (having an air cylinder), providesmeans for raising and lowering the common lift pin element. Substrate325 can be transferred into and out of process chamber 310 through agate valve (not shown) and chamber feed-through passage, aligned on thetransfer plane, via a robotic transfer system (not shown), and receivedby the substrate lift pins. Once the substrate 325 is received from thetransfer system, it can be lowered to the upper surface of the pedestal320 by lowering the substrate lift pins 372 (see FIGS. 3A and 4A).Moreover, the substrate 325 may be raised above substrate holder 320during the heating of substrate 325 (see FIGS. 3B and 4B). The substratelift pins 372 may comprise pin caps 374 fabricated from a thermallyinsulating material, such as quartz or sapphire, in order to thermallydecouple the substrate 325 from the substrate lift pins 372.

Further yet, substrate holder assembly 320 comprises a backside gassupply system 364 configured to supply a heat transfer gas, or a purgegas, or both to the backside of substrate 325. During chemical treatmentof substrate 325, the substrate 325 can be clamped to substrate holder320 using ESC system 380 while the backside gas supply system 364supplies heat transfer gas, such as helium, to the backside of substrate325 in order to improve the thermal contact between substrate 325 andsubstrate holder 320 (see FIGS. 3A and 4A). The substrate temperaturecontrol system can then be utilized to adjust the temperature ofsubstrate 325. During the thermal treatment of substrate 325, thesubstrate 325 can be raised above the substrate holder using thesubstrate lift system 370 while the backside gas supply system 364supplies a purge gas flow 390 to the backside of substrate 325 in orderto reduce contamination of the substrate backside (see FIGS. 3B and 4B).

During chemical treatment of substrate 325, substrate 325 rests onsubstrate holder 320 and the temperature is controlled to a chemicaltreatment temperature less than approximately 100 degrees C. while thesubstrate 325 is exposed to process gas configured to chemically alteroxide material on substrate 325. During chemical treatment, substrate325 may be clamped to the substrate holder 320 using ESC system 380 anda flow of backside gas can be initiated from backside gas supply system364 in order to affect improved thermal conductance between thesubstrate 325 and the substrate holder 320 (see FIGS. 3A and 4A).

Following the chemical treatment of substrate 325, the temperature ofsubstrate 325 is elevated using a radiative heating system 330 abovesubstrate 325 in order to desorb the chemically altered oxide material.During the thermal treatment of substrate 325, the substrate 325 can beraised above substrate holder 320 and displaced from the substrateholder 320 using substrate lift system 362 by a distance sufficient tosubstantially thermally decouple the substrate 325 from substrate holder320. Furthermore, the substrate 325 may be lifted to close proximitywith the radiative heating system 330 in order to reduce the extent towhich other chamber components see the radiative heating system 330during heating. Preferably, substrate 325 is heated while other chambercomponents are not. Additionally, when substrate 325 is raised abovesubstrate holder 320, an optional flow of purge gas from backside gassupply system 364 can be conducted in order to reduce contamination ofthe backside of substrate 325 during the desorption process (see FIGS.3B and 4B).

Furthermore, referring to FIGS. 4A and 4B, a radiation shield 332 may beutilized to reduce the heating of other chamber components during theheating of substrate 325. Substrate 325 can, for example, be lifted toclose proximity with the bottom of radiation shield 332. The radiationshield 332 may comprise one or more openings 334 in order to permit thepassage of gaseous material originating from substrate 325 duringheating. Additionally, a purge gas, such as an inert gas (e.g., a noblegas, N₂, etc.), can be introduced to the space enclosed by radiationshield 332, substrate 325 and radiative heating system 330 duringthermal treatment of substrate 325. Furthermore, the radiation shieldmay be coupled to the upper portion of process chamber 310. Theradiation shield may be a bare metal shield or a ceramic shield, or itmay be an anodized metal shield or coated metal shield, for example.

Referring again to FIG. 2, vacuum pumping system 250 can comprise avacuum pump and a gate valve for adjusting the chamber pressure. Vacuumpumping system 250 can, for example, include a turbo-molecular vacuumpump (TMP) capable of a pumping speed up to about 5000 liters per second(and greater). For example, the TMP can be a Seiko STP-A803 vacuum pump,or an Ebara ET1301W vacuum pump. TMPs are useful for low pressureprocessing, typically less than about 50 mTorr. For high pressure (i.e.,greater than about 100 mTorr) or low throughput processing (i.e., no gasflow), a mechanical booster pump and dry roughing pump can be used.

Referring still to FIG. 2, treatment system 200 can further comprise acontroller 270 having a microprocessor, memory, and a digital I/O portcapable of generating control voltages sufficient to communicate andactivate inputs to treatment system 200 as well as monitor outputs fromtreatment system 200 such as temperature and pressure sensing devices.Moreover, controller 270 can be coupled to and can exchange informationwith substrate holder 220, chemical distribution system 240, gas supplysystem 242, radiative heating system 230, vacuum pumping system 250,substrate temperature control system 260, substrate lift system 262, andbackside gas supply system 264. For example, a program stored in thememory can be utilized to activate the inputs to the aforementionedcomponents of treatment system 200 according to a process recipe. Oneexample of controller 270 is a DELL PRECISION WORKSTATION 610™,available from Dell Corporation, Austin, Tex.

The controller 270 may also be implemented as a general purposecomputer, processor, digital signal processor, etc., which causes asubstrate processing apparatus to perform a portion or all of theprocessing steps of the invention in response to the controller 290executing one or more sequences of one or more instructions contained ina computer readable medium. The computer readable medium or memory forholding instructions programmed according to the teachings of theinvention and for containing data structures, tables, records, or otherdata described herein. Examples of computer readable media are compactdiscs, hard disks, floppy disks, tape, magneto-optical disks, PROMs(EPROM, EEPROM, flash EPROM), DRAM, SRAM, SDRAM, or any other magneticmedium, compact discs (e.g., CD-ROM), or any other optical medium, punchcards, paper tape, or other physical medium with patterns of holes, acarrier wave, or any other medium from which a computer can read.

The controller 270 may be locally located relative to the treatmentsystem 200, or it may be remotely located relative to the treatmentsystem 200 via an internet or intranet. Thus, the controller 270 canexchange data with the treatment system 200 using at least one of adirect connection, an intranet, and the internet. The controller 270 maybe coupled to an intranet at a customer site (i.e., a device maker,etc.), or coupled to an intranet at a vendor site (i.e., an equipmentmanufacturer). Furthermore, another computer (i.e., controller, server,etc.) can access controller 270 to exchange data via at least one of adirect connection, an intranet, and the internet.

Referring now to FIG. 5, a method of performing a dry non-plasmatreatment of a substrate is presented according to an embodiment. Thetreatment process can, for example, include a process for removing oxidematerial on the substrate. The dry, non-plasma treatment processincludes a chemical process during which exposed surfaces of a substratehaving an oxide material are chemically treated by a process gascomprising HF, or ammonia (NH₃), or both HF and NH₃ as incipientingredients. Exposure to incipient HF and/or NH₃ can remove oxidematerial, such as oxidized silicon (or SiO_(x)), and/or consume oxidematerial by displacing such material with a chemically treated material.The self limiting feature results from a reduced rate of removal and/orchemical altering of the oxide material as exposure to the processmaterial proceeds.

Following the chemical treatment process, a desorption process isperformed in order to remove the chemically altered surface layers. Dueto the self-limiting feature of the chemical treatment process, it maybe desirable to alternatingly perform the non-plasma etch and subsequentdesorption process, which can allow precise control of the removalprocess. The desorption process can comprise a thermal treatment processwithin which the temperature of the substrate is raised sufficientlyhigh to permit the volatilization of the chemically altered surfacelayers.

The method includes a flow chart 500 beginning in step 510 withdisposing the substrate in a treatment system configured to facilitatethe chemical and desorption processes. For example, the treatment systemcomprises one of the systems described in FIG. 1 or 2.

In step 520, oxide material on the substrate is chemically treated.During the chemical treatment process of the dry non-plasma treatment,each constituent of the process gas may be introduced together (i.e.,mixed), or separately from one another (i.e., HF introducedindependently from NH₃). Additionally, the process gas can furtherinclude an inert gas, such as a noble gas (i.e., argon). The inert gasmay be introduced with either the HF or the NH₃, or it may be introducedindependently from each of the aforementioned gaseous constituents.Further details regarding the introduction of a noble gas with NH₃ inorder to control the removal of silicon dioxide is described in pendingU.S. patent application Ser. No. 10/812,347, entitled “Processing Systemand Method For Treating a Substrate”, the entire contents of which areherein incorporated by reference in their entirety.

Additionally, during the chemical treatment process, the processpressure may be selected to affect the amount of oxide material removed.The process pressure can range from approximately 1 mtorr toapproximately 100 torr. Furthermore, during the chemical treatmentprocess, the substrate temperature may be selected to affect the amountof oxide material removed. The substrate temperature can range fromapproximately 10 degrees C. to approximately 200 degrees C., or thesubstrate temperature can be less than 100 degrees C. For example, thetemperature can range from approximately 10 degrees C. to 50 degrees C.Further details regarding the setting of the substrate temperature inorder to control the removal amount is described in pending U.S. patentapplication Ser. No. 10/817,417, entitled “Method and System ForPerforming a Chemical Oxide Removal Process”, the entire contents ofwhich are herein incorporated by reference in their entirety.

In step 530, chemically altered oxide material on the substrate isthermally treated. During the thermal treatment process, the substratetemperature can be elevated above approximately 50 degrees C., or aboveapproximately 100 degrees C. Additionally, an inert gas may beintroduced during the thermal treatment of the substrate. The inert gasmay include a noble gas or nitrogen.

Additionally, during the chemical and thermal treatments of thesubstrate, the process chamber can be configured for a temperatureranging from about 10° to about 450° C. Alternatively, the chambertemperature can range from about 30° to about 60° C. The temperature forthe substrate can range from approximately 10° to about 450° C.Alternatively, the substrate temperature can range form about 30° toabout 60° C.

In one example, part of or all of an oxide film, such as a native oxidefilm, is removed on the substrate using a chemical oxide removalprocess. In another example, part of or all of an oxide film, such as anoxide hard mask, is trimmed on a substrate using a chemical oxideremoval process. The oxide film can comprise silicon dioxide (SiO₂), ormore generally, SiO_(x), for example. In yet another example, part orall of a SiO_(x)-containing residue is removed on the substrate.

Although only certain embodiments of this invention have been describedin detail above, those skilled in the art will readily appreciate thatmany modifications are possible in the embodiments without materiallydeparting from the novel teachings and advantages of this invention.Accordingly, all such modifications are intended to be included withinthe scope of this invention.

The invention claimed is:
 1. A treatment system for removing material ona substrate, comprising: a temperature controlled process chamberconfigured to contain a substrate and configured to facilitate anon-plasma environment, said substrate having a surface oriented to betreated by said non-plasma environment; a temperature controlledsubstrate holder mounted within said temperature controlled processchamber, and configured to support said substrate, orient said substratesuch that said surface is exposed to said non-plasma environment, andcontrol a temperature of said substrate when said substrate is restingon an upper surface of said temperature controlled substrate holder; avacuum pumping system coupled to said temperature controlled processchamber; a chemical treatment system coupled to said temperaturecontrolled process chamber and configured to introduce a process gas tosaid temperature controlled process chamber, wherein said process gaschemically alters at least a portion of said surface on said substrateexposed to said non-plasma environment, wherein said process gascomprises as incipient ingredients HF and optionally ammonia (NH₃); athermal treatment system, separate from said temperature-controlledsubstrate holder, coupled to said temperature controlled process chamberand configured to elevate the temperature of said substrate in saidtemperature controlled process chamber, wherein said elevatedtemperature causes evaporation of said chemically altered surfacelayers, and wherein said thermal treatment system comprises one or moreradiative heat lamps arranged to directly irradiate said surface of saidsubstrate that is exposed to said non-plasma environment; and acontroller coupled to said temperature controlled substrate holder, saidchemical treatment system, and said thermal treatment system andconfigured to control the amount of said process gas introduced to saidsubstrate, and the temperature to which said substrate is set.
 2. Thetreatment system of claim 1, further comprising: a substrate lift systemcoupled to said temperature controlled substrate holder and configuredto vertically transfer said substrate to and from said upper surface ofsaid temperature-controlled substrate holder and to and from a heatingplane located above said upper surface of said temperature controlledsubstrate holder when heating said substrate using said thermaltreatment system.
 3. The treatment system of claim 1, wherein saidprocess gas comprises as incipient ingredients HF and ammonia (NH₃), andwherein said HF is introduced independently from said ammonia.
 4. Thetreatment system of claim 1, wherein said process gas chemically altersexposed surface layers on said substrate to a self-limiting depth. 5.The treatment system of claim 1, wherein said thermal treatment systemcomprises a multi-zone lamp heating system.
 6. The treatment system ofclaim 1, wherein said controller is: configured to operate saidtreatment system to both chemically treat said substrate and, followingsaid chemical treatment, thermally treat said substrate in saidtemperature-controlled process chamber, wherein during said chemicaltreatment and said thermal treatment, said controller is configured tomonitor, adjust, or control the temperature of said substrate or anamount of said process gas in said temperature controlled processchamber, or any combination thereof.
 7. The treatment system of claim 1,wherein said substrate comprises an oxide material or residue to beremoved in said treatment system.
 8. The treatment system of claim 1,wherein said chemical treatment system comprises a multi-zone fluiddistribution system configured to adjust the flow of said process gas tomultiple zones within said temperature controlled process chamber. 9.The treatment system of claim 1, wherein said chemical treatment systemis further configured to supply a carrier gas with said process gas. 10.The treatment system of claim 9, wherein said carrier gas comprises aninert gas.
 11. The treatment system of claim 2, further comprising: abackside gas supply system coupled to said temperature controlledsubstrate holder and configured to supply a purge gas to the backside ofsaid substrate when said substrate is lifted above said upper surface ofsaid temperature controlled substrate holder in order to reducecontamination of the backside of said substrate.
 12. The treatmentsystem of claim 2, further comprising: a radiation shield coupled tosaid temperature controlled process chamber and configured to surround aperipheral edge of said thermal treatment system, wherein said radiationshield, said thermal treatment system and said substrate in said raisedposition form a substantially closed space, and wherein said thermaltreatment system comprises one or more radiative heat lamps arrangedabove said substrate.
 13. The treatment system of claim 12, wherein saidradiation shield comprises one or more openings there-through in orderto permit the passage of gases.